Sizing hydronic baseboard

My bathroom reno is almost done, save for a vanity I have to replace an existing wall-mounted accessible sink. There's about a 3.5' length of baseboard in the way. I was going to remove the baseboard, cut it down with snips, add a notch to the back of the vanity to clear the copper, and install it. But I'm thinking I really don't need any of that length. The bathroom is only 64 sq ft, and the adjacent wall already has a 6' length. I'd rather verify that that section is not needed, and redirect the pipe under the floor. To that end, I found that Warmly Yours has a comprehensive heat load calculator. I came up with this:

With most baseboards putting out 400-500 BTU/h/ft, it seems like the one ~6' section should be more than enough. I'm guessing the installer used some old-school method that overcompensate or assumes a lack of insulation, or perhaps there is/was some rule that you have to have baseboard on every exterior wall. The wall behind the sink is indeed on the exterior wall. Considering the alternative of having only about 18" of operational baseboard*, what would y'all recommend?

* Because I'm not that big on pedestal sinks, and need the vanity storage space so a pedestal is not an option. Oh, and I already have the new vanity.

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Sizing hydronic baseboard

It ws probably put there to help prevent the hot and old water pipes from freezing over night when no water is used for 8 or more hours, on the coldest nights. If that wall is insulated well, you shouldn't need it.

Sizing hydronic baseboard

Well, it's a 2x6 wall with R16 or R17 batts in it (I forget the exact rating, it was Johns Manville fiberglass when I cut a hole for an electrical box), the ceiling is R45 (except around the skylight) and the baseboard I plan on retaining is on the wall adjacent to the sink. I'm thinking the guy was just overcompensating. You should see the upstairs bathroom in the original stone section. There is literally baseboard on every possible wall-- the only places without it are occupied by the toilet, door, or tub. He might not have been too confident in the insulation up there.